检索结果-南通市图书馆

Forestry Studies in China 2012年第3期14卷 187-192页

作者： bhupendra SINGH Rajendra YADAV b.p. bhatt Department of Forestry H.N.B.Garhwal UniversitySrinagar (Garhwal)Uttarakhand 246174India Chhattisgarh Minor Forest produce Federation A-25VIP EstateKhamhardihShankar NagarRaipur 492007India ICAR Research Complex for Eastern Region PatnaBihar 800014India

The effect of auxins （IAA or IbA at 100, 200, 500 mg.L J） on rooting and sprouting parameters differed significantly （p 〈 0.05）. Rooting and sprouting percentages were higher in some treatments while other parameters were significantly higher in other treatments. The results of the present study revealed that rooting was significantly （p 〈 0.05） affected by the length of cuttings, as well as the position of shoots and type of cuttings. On average, 86.0 per cent rooting was observed in the 30-cm long cuttings com- pared to the other two lengths of cuttings, i.e., 20 and 25 cm, irrespective of any auxin treatment. In a control set, without any auxin treatment, a maximum of 60.0% rooting was recorded in the 30-cm long cuttings and a minimum of 40.0% of the cuttings rooted in the 20-cm long cuttings. Similarly, cuttings collected from the lower and upper portions of shoots resulted in 72.5 and 52.5 per cent rooting respectively, irrespective of auxin treatments. Maximum rooting was observed in the lower portion （40.0%） of cutting com- pared to the upper portion （30.0%） in the control set without auxin treatment. Leafless branches produced maximum （72.0%） rooting compared to the leafy cuttings （35.0%）, irrespective of the auxin treatment. The leafy cuttings produces a minimum of 15.0% sprout- ing and rooting in the control set.

关键词： auxin Dalbergia sissoo length position of shoots type of cuttings vegetative propagation

Thermophysical properties of iridium at finite temperature

在线全文

学校读者我要写书评

暂无评论

Chinese physics b 2016年第11期25卷 404-411页

作者： priyank Kumar N K bhatt p R Vyas V b Gohel Department of Science Government PolytechnicGandhinagar Department of physics Sardar Patel University Department of physics School of Science Gujarat University

The bulk properties of materials in an extreme environment such as high temperature and high pressure can be understood by studying anharmonic effects due to the vibration of lattice ions and thermally excited *** this spirit,in the present paper,anharmonic effects are studied by using the recently proposed mean-field potential（MFp） approach and Mermin functional which arise due to the vibration of lattice ions and thermally excited electrons,*** MFp experienced by a wanderer atom in the presence of surrounding atoms is constructed in terms of cold energy using the local form of the *** have calculated the temperature variation of several thermophysical properties in an extreme environment up to melting *** results of our calculations are in excellent agreement with the experimental findings as well as the theoretical results obtained by using first principle *** conclude that presently used conjunction scheme（MFp＋pseudo potential） is simple computationally,transparent physically,and accurate in the sense that the results generated are comparable and sometimes better than the results obtained by first principle *** pseudopotential used is transferable to extreme environment without adjusting its parameters.

关键词： extreme experienced melting presently excited thermally sometimes understood comparable conclude

High-temperature thermodynamics of silver:Semi-empirical approach

在线全文

学校读者我要写书评

暂无评论

Chinese physics b 2017年第11期26卷 400-407页

作者： R H Joshi b Y Thakore p R Vyas A R Jani N K bhatt Department of physics Sardar Patel University Department of physics School of Sciences Gujarat University Sardar patel Center for Science and Technology Department of physics M.K.Bhavnagar University

We report high-temperature thermodynamics for fcc silver by combining ab initio phonon dynamics to empirical quadratic temperature-dependent term for anharmonic part of Helmholtz free energy. The electronic free energy is added through an interpolation scheme, which connects ambient condition free electron gas model to Thomas-Fermi *** present study shows good agreement with experimental and reported findings for several thermal properties, and the discrepancy observed in some caloric properties is addressed. The decreases in the product of volume thermal expansion coefficient and isothermal bulk modulus and in the constant volume anharmonic lattice specific heat at high temperature are the clear evidences of proper account of anharmonicity. The present study also reveals that T-2-dependent anharmonic free energy is sufficient for correct evaluation of thermal pressure and conventional Grüneisen parameter. We observe that the intrinsic phonon anharmonicity starts dominating above characteristic temperature, which is attributed to higher order anharmonicity and can be related to higher order potential derivatives. We conclude that the uncorrelated and largeamplitude lattice vibrations at high temperature raise dominating intrinsic thermal stress mechanism, which surpasses the phonon-anharmonism and requires future consideration.

关键词： thermodynamics anharmonicity Grüneisen parameter silver

Structural and mass transport properties of liquid ytterbium in the temperature range 1123 K–1473 K

在线全文

学校读者我要写书评

暂无评论

Chinese physics b 2023年第6期32卷 481-488页

作者： D D Satikunvar N K bhatt b Y Thakore Department of physics Sardar Patel UniversityVallabh VidyanagarGujarat 388120India Department of physics Maharaja Krishnakumarsinhji Bhavnagar UniversityBhavnagarGujarat 364001India

We have studied the structural and atomic transport properties of liquid f-shell Yb in the temperature range 1123 K–1473 K. pair interactions between atoms are derived using a local pseudopotential. The potential parameters are fitted to the phonon dispersion curve at room temperature. The local pseudopotential used in the present study is computationally more efficient with only three parameters, and it is found to be transferable to the liquid phase without changing the *** the various computed properties agree with reported theoretical and experimental findings, the adopted fitting scheme is justified. As a significant outcome of the study, we find that(i) the melting in Yb is governed by the Lindemann's law,(ii)the mass transport mechanism obeys the Arrhenius law,(iii) the role of the three-particle correlation function in deriving the velocity autocorrelation function is small,(iv) the mean-square atomic displacement is more sensitive to the choice of interaction potential than the other bulk properties, and(v) liquid Yb does not show liquid–liquid phase transition within the studied temperature range. Further, due to the good description of the structural and mass transport properties, we propose that Yb remains divalent at reduced density.

关键词： transport properties pseudopotential single-particle dynamics ytterbium

Effects of mother tree ages, different rooting mediums, light conditions and auxin treatments on rooting behaviour of Dalbergia sissoo branch cuttings

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2011年第1期22卷 53-57页

作者： bhupendra Singh Rajendra Yadav b. p. bhatt Department of Forestry Post Box No-59 H.N.B. Garhwal University Srinagar Garhwal - 246 174 Uttarakhand India Chhattisgarh Minor Forest produce Federation A-25 VIP Estate Khamhardih Shankar Nagar Raipur- 492 007. ICAR Research Complex for NEH Region Nagaland Centre Medziphema- 797 106 Nagaland India

Dalbergia sissoo Roxb. is one of the promising multipurpose tree species of South Asia. Most of the plantations of D. sissoo from seeds are facing severe threats due to the die-back disease, which ultimately causes death of this potential tree-species within a few months. Vegetative propagation could avoid the die-back disease. Thirty mother trees of different age-groups of D. sissoo were selected for evaluating the rooting behaviour of branch cuttings from D. sissoo as influenced by auxins （IAA or IbA at 100, 200, 500 mg·L^-1）, ages of mother trees （10, 4 and 2 years old） and different environment conditions, i.e., different mediums （soil and sand） or light conditions （in shade and open condition）. The results show that application of IAA and IbA induced more numbers of cuttings （collected from 10-year-old mother trees） to root compared to control. branch cuttings of D. sissoo collected from 10-year-old mother trees and planted in soil bed in open conditions had 100.0% of cuttings to root in IAA （100 mg·L^-1） and IbA （200 mg·L^-1） treatments. both rooting medium （Soil and sand） influenced significantly （p〈0.05） on rooting response of branch cuttings. Soil medium was found to achieve maximum no. of branch cuttings to root, compared to sand medium.

关键词： Dalbergia sissoo hormonal treatments rooting medium shading vegetative propagation branch cutting

Community and hospital acquired methicillin resistant Staphylococcus aureus efficiently retain the Van A determinant

在线全文

学校读者我要写书评

暂无评论

Frontiers in biology 2015年第6期10卷 520-527页

作者： Anup Kainthola Ajay b. bhatt Ashish Gupta Laboratory of Microbiology Department of Botany & Microbiology HNB Garhwal Central University Uttarakhand 246174 India School of biotechnology Amity International University NOIDA UP India

Dissemination of vancomycin resistance from hospital to community strains is a serious threat to public health. Our study aimed to provide evidence for transmission of Van A type resistance from the hospital to the community. Wild-type community and hospital associated methicillin resistant Staphylococcus aureus strains were studied in vitro and in a model that mimicked a natural environment to ascertain their ability to acquire and maintain the vancomycin resistance determinant （Van A gene） from vancomycin resistant Enterococcus faecalis. Fitness was assessed and the cost of Van A acquisition and retention was estimated. In vitro mating experiments were carried out using a filter mating technique and a model of a natural water body environment. Transfer of resistance was carried out in two different conditions： restricted and favorable. Transconjugants were confirmed by E test and pCR using specific primer sets. Growth kinetics and fitness measurements were done by spectrometric analysis. Using the in vitro filter mating technique, high transfer frequencies that ranged from 0.7 × 10^-3（0.0006） to 3.1 ×10^-4（0.00011） were recorded, with the highest transfer frequencies for CA MRSA （thermosensitively homogenous）（0.7 × 10^- 3）, and 1.2 × 10^-4 to 2.4 × 10^-4 in the model. HA MRSA （homogenous） showed a greater capacity （3.6 ×10^-4） to receive the Van A gene, while CA MRSA showed a reduced ability to maintain the gene after serial subcultures. CA and HA thermosensitively heterogeneous MRSA transconjugants exhibited higher growth rates. The present study provides evidence for the enhanced ability of CA and HA MRSA clones to acquire and maintain Van A type resistance.

关键词： Van A resistance MRSA fitness growth kinetics resistance transfer

Current Vegetation pattern along Glacial Landscape in Central (Garhwal) Himalaya, India

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Mountain Science 2005年第3期2卷 255-264页

作者： Uday N. Gaur G.p. Raturi A.b. bhatt Department of botany HNB Garhwal University Srinagar Garhwal- 246 174 (Uttaranchal) India Department of Botany HNB Garhwal University Srinagar Garhwal- 246 174 (Uttaranchal) IndiaDepartment of Botany HNB Garhwal University Srinagar Garhwal- 246 174 (Uttaranchal) India

Current vegetation patterns, biodiversity and adaptation of plants were studied during 1998-2001 in glacial landscape of Chaurabari situated above Kedarnath （30° 44＇ N- 79° 07＇ E; 3,000- 6,000 m） in Central Himalaya. Landscape was identified into different zones on account of the vegetation status, glacial features, geomorphology and altitudes. Cold environment with heavy snowfall, frost hailstorm and dense frost characterizes the study area predominance of the soda rich feldspars indicates soda enrichment; orthoclase, microcline weathering and alternation would have contributed potash to the soil. The increasing severity of the environment as we ascend from timberline to snowline leads to progressive decline in the abundance and diversity of the plant species. The diversity of the higher plants decrease, while the diversity of microflora increase from alpine zone to snowline zone. Highly opulent and diverse flora with beautiful, delicate herbs occupy the alpine zone, but some specialized groups of the plants, particularly high energetic and cold resistant species reside in glacial environment. Asteraceae, Rananculaceae, primulaceae, Rosaceae, Apiaceae and Ericaceae are the pioneer angiospermic families, while Anaphalis triplinervis, A. royleana, Androsacce sarmentosa, Cotoneaster rotundifolius,Lonicera myrtillus, Cassiope fastigiata, Gaultheria trichophylla and Erigeron multiradiatus are the pioneer species, which have invaded in glacial environment. Through its nature, alpine glacial ecotone can be seen easily due to environmental and edaphic differences.

关键词： Glacial ecosystem vegetation pattern plant diversity

population structure and regeneration patterns of tree species in climate-sensitive subalpine forests of Indian western Himalaya

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2014年第2期25卷 343-349页

作者： Sanjay Gairola R. S. Rawal N. p. Todaria Arvind bhatt School of Agricultural Earth and Environmental SciencesUniversity of KwaZulu-NatalWestville Campus G.b. pant Institute of Himalayan Environment and Development Department of Forestry and Natural Resources H.N.B. Garhwal University School of Life Sciences University of KwaZulu-NatalWestville Campus

The population structure of tree species has been explored in order to elucidate regeneration potential of the subalpine forests of Indian western Himalaya. For this study, the subalpine forest area was divided into three strata, i.e., lower altitude （〈3000 m）; mid-altitude （3000-3200 m）; and high altitude （〉3200m）. Considering the major compositional attributes, an increase in altitude came with a significant decline in tree density and the total basal area for all the sites. However, no such clear trends were observed for recruits （i.e., seedlings and saplings）. Seedling density did not exhibit uniform patterns for sites and altitude strata. In general, overall seedling density was greater at the pindari site compared to the Lata and Tungnath sites. by comparison, significant variation in seedling density along the altitude strata was recorded for the Tungnath and pindari sites only. Likewise, sapling density patterns varied across the sites and altitude strata, and significant variation in sapling density along the altitude strata was recorded only for the Lata site. At the pin- daft site, the continuous increase in sapling density along with increasing altitude was revealing. The pindari forests of exhibited expanding population structure. In contrast, greater accumulation of individuals in the sapling class and sharp decline toward both higher tree classes and lower seedling classes was generally apparent for the Lata and Tungnath sites. This indicates that the replacement in tree size classes from sapling stage is not proportional and the population may decline in the long-term. Considerable variation in patterns of forest and dominant species popula- tion structure were evident across altitude strata. but in all cases irrespective of sites, we found growth at the high-altitude stratum, in the form of entire forests or dominant species. This trend deserves further investigation to explore its relevance under changing climate scenarios.

关键词： population structure regeneration subalpine forest altitude

Thermodynamic properties of 3C-SiC

在线全文

学校读者我要写书评

暂无评论

Chinese physics b 2013年第10期22卷 429-435页

作者： b.Y.Thakore S.G.Khambholja A.Y.Vahora N.K.bhatt A.R.Jani Department of physics Sardar Patel UniversityVallabh Vidyanagar388120GujaratIndia Indus University Ahmedabad 380001GujaratIndia

In the present paper, we report on the results of various thermodynamic properties of 3C-SiC at high pressure and temperature using first principles calculations. We use the plane-wave pseudopotential density functional theory as im- plemented in Quantum ESpRESSO code for calculating various cohesive properties in ambient condition. Further, ionic motion at a finite temperature is taken into account using the quasiharmonic Debye model. The calculated thermody- namic properties, phonon dispersion curves, and phonon densities of states at different temperatures and structural phase transitions at high pressures are found to be in good agreement with experimental and other theoretical results.

关键词： phase transition phonon dispersion curve Debye model thermodynamic property

Effect of compressibility on bubbly cavitating flows

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2020年第1期32卷 1-5页

作者： Harish Ganesh Anubhav bhatt Juliana Wu Steven Ceccio Department of Naval Architecture and Marine Engineering University of MichiganAnn ArborMichiganUSA

Cavitating bubbly flows can form in separated flows and shear layers leading to local regions high vapor void fraction,and these flows often exhibit periodic shedding of vaporous ***,the presence of a liquid re-entrant flow,driven by the kinematics of liquid flow stagnation,has been identified as an important mechanism leading to cavity ***,high local vapor void fractions can also result in a reduced mixture speed of sound and a possible supersonic *** recent findings on different geometries indicate that propagating bubbly shocks in these flows are a primary mechanism of flow *** this study,we discuss the effect of compressibility on four geometries,mainly in the generation of propagating bubbly shocks that can influence the cavitation shedding *** order to elucidate the differences and similarities of the observed cavitation dynamics,and the influence of compressibility,we report observations from a backward facing step,backward facing wedge,NACA0015 hydrofoil,and a bluff body with a wedge cross section.

关键词： Cavitation bubbly shocks compressible vapor-liquid flows